From quaternions to OpenGL rotations

Question

I have an object which I want to rotate via keys. The object should yaw, pitch and roll. After trying a lot, I figured out that glRotate has its limitations and

Answer 1

You can easily build rotation matrices out of unit quaternions.

Given a unit quaternion a + bi + cj + dk, you can build the following 3x3 matrix:

Add the last line and column taken from the identity 4x4 matrix, glMultMatrix and you're done :)